Liz Carlyle, MI5's liaison with French intelligence, investigates Birmingham's New Springfield mosque, which has disturbing ties to Pakistan and terrorism. Meanwhile, UCSO in Athens, worried that its ships are being specifically targeted by pirates, wonders if there's a leak in the organization.

When a Russian intelligence officer insists on speaking to no one but her about cyber sabotage that has brought down a U.S. communications satellite, MI5 agent Liz Carlyle learns of a plot to hack into the West's military and reignite the Cold War.

"Kidnapped in Venice by a Russian defector, Kate knows she's in trouble. But when he offers her conclusive evidence that the British Prime Minister is a live agent working for Moscow, Kate's holiday quickly becomes the start of her next mission. The defector has proof of the PM involved in a sordid scandal-a video supposedly used to blackmail him into Russian service decades prior-and a financial paper trail that undeniably links him to the Russians,...

Eve is on a revenge mission while Villanelle has embraced a brand-new way of life in an attempt to prove she's not a 'monster, 2 all while Carolyn goes to extraordinary lengths to continue to chase down the Twelve.

"After five years' silence, a British intelligence asset has made contact from Moscow. Claiming to be in possession of an explosive piece of information, he wishes to defect to the West. The carefully-planned operation however goes catastrophically wrong, the would-be defector ruthlessly betrayed by a rogue element at the highest level of US government. As a result, MI6's Margo Lane is ordered to deliver a message the White House won't forget. It's...